I wrote up a guide for installing add-ons to adjust the site skin.

It includes links to Stylish and Greasemonkey type add-ons for both Firefox and Chrome, as well a style that will modify the default site scheme (and the related purple version) so that the text stretches across the browser, the bg is white, and the font size is bigger (same size as before LJ's update).

Also, if you're bored and want to poke at DW more
Collection of resource links and guides/FAQs
dreamwidthlayouts has some custom layouts that work with DW themes (as well as flexible square layouts and etc...)